package org.ecloud.core.utils;

import java.net.InetAddress;
import java.net.UnknownHostException;

import javax.servlet.http.HttpServletRequest;

import org.ecloud.utils.BeanUtil;
import org.ecloud.utils.StringUtil;

public class RequestUtil {

	/**
	 * 获取IP地址 不使用request.getRemoteAddr();的原因是有可能用户使用了代理软件方式避免真实IP地址,<br>
	 * 
	 * 可是，如果通过了多级反向代理的话，X-Forwarded-For的值并不止一个，而是一串IP值，究竟哪个才是真正的用户端的真实IP呢？
	 * 答案是取X-Forwarded-For中第一个非unknown的有效IP字符串。
	 * 
	 * 如：X-Forwarded-For：192.168.1.110,192.168.1.120,192.168.1.130,192.168.1.100
	 * 
	 * 用户真实IP为： 192.168.1.110
	 * 
	 * @param request
	 * @return
	 */
	public static String getIpAddr(HttpServletRequest request) {
		if(BeanUtil.isEmpty(request))
			return "未获得request";
		String ipAddress = request.getHeader("X-Forwarded-For");
		if (StringUtil.isBlank(ipAddress) || "unknown".equalsIgnoreCase(ipAddress)) {
			ipAddress = request.getHeader("X-Real-IP");
		}
		if (StringUtil.isBlank(ipAddress) || "unknown".equalsIgnoreCase(ipAddress)) {
			ipAddress = request.getHeader("Proxy-Client-IP");
		}
		if (StringUtil.isBlank(ipAddress) || "unknown".equalsIgnoreCase(ipAddress)) {
			ipAddress = request.getHeader("WL-Proxy-Client-IP");
		}
		if (StringUtil.isBlank(ipAddress) || "unknown".equalsIgnoreCase(ipAddress)) {
			ipAddress = request.getHeader("HTTP_CLIENT_IP");
		}
		if (StringUtil.isBlank(ipAddress) || "unknown".equalsIgnoreCase(ipAddress)) {
			ipAddress = request.getHeader("HTTP_X_FORWARDED_FOR");
		}
		if (StringUtil.isBlank(ipAddress) || "unknown".equalsIgnoreCase(ipAddress)) {
			ipAddress = request.getRemoteAddr();
			if ("127.0.0.1".equals(ipAddress) || "0:0:0:0:0:0:0:1".equals(ipAddress)) {
				InetAddress inet = null; // 根据网卡取本机配置的IP
				try {
					inet = InetAddress.getLocalHost();
					ipAddress = inet.getHostAddress();
				} catch (UnknownHostException e) {
				}
			}
		}
		// 对于通过多个代理的情况，第一个IP为客户端真实IP,多个IP按照','分割
		if (StringUtil.isNotBlank(ipAddress) && ipAddress.length() > 15) { // "***.***.***.***".length()=15
			if (ipAddress.indexOf(",") > 0)
				ipAddress = ipAddress.substring(0, ipAddress.indexOf(","));
		}
		return ipAddress;
	}
	
}
